Publish to gh packages maven

[LeafHacker]

Is your feature request related to a problem? Please describe. It'd be good to transition away from the github repo being misused as a maven repository. This allows us to use publishing tasks to publish artifacts to maven without having to mess about with cloning the repo locally and committing to it after a publish.

Describe the solution you'd like A publishing task that publishes artifacts to a github package registary maven repo. Preferably one shared by all public impact projects.

[leijurv]

installer on github package registry = 👍